1. What is Pressure Drop Calculation?

Definition: This calculator estimates the pressure loss in a pipe due to friction between the fluid and the pipe walls.

Purpose: It helps engineers and technicians determine the pressure loss in piping systems for proper system design.

2. How Does the Calculator Work?

The calculator uses the Darcy-Weisbach equation:

Where:

• \( \Delta P \) — Pressure drop (psi)
• \( f \) — Darcy friction factor (dimensionless)
• \( L \) — Pipe length (ft)
• \( \rho \) — Fluid density (lb/ft³)
• \( V \) — Flow velocity (ft/s)
• \( D \) — Pipe diameter (ft)

Explanation: The equation calculates the pressure loss due to friction in a straight pipe section.

3. Importance of Pressure Drop Calculation

Details: Proper pressure drop estimation ensures adequate pump sizing, proper system operation, and energy efficiency.

4. Using the Calculator

Tips: Enter the friction factor (typically 0.01-0.05), pipe length, fluid density (62.4 lb/ft³ for water), flow velocity, and pipe diameter. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How do I determine the friction factor?
A: The friction factor depends on pipe roughness and Reynolds number. For turbulent flow in smooth pipes, it's typically 0.02-0.03.

Q2: What units should I use?
A: All inputs must be in consistent units: feet for length/diameter, lb/ft³ for density, ft/s for velocity.

Q3: Does this include fittings losses?
A: No, this calculates only straight pipe losses. Additional losses from valves/fittings must be calculated separately.

Q4: What's a typical flow velocity?
A: For water systems, 2-10 ft/s is common, with 5-8 ft/s being typical for balance of efficiency and noise.

Q5: How accurate is this calculation?
A: It provides a good estimate for turbulent flow. Accuracy depends on correct friction factor selection.